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Climate Shocks and Human Capital

The Impact of Natural Disasters on Students’ Performance in Standardized Tests

Mauricio Giovanni Valencia Amaya

1

Abstract

Using a difference-in-difference approach with repeated cross-sections, this paper investigates the impact of the climate shocks occurred in Colombia in 2010 on the results in the country’s state standardized test, “Pruebas Saber 11”, during the period 2010-2012. Even though cognitive skills variables have been recognized as better proxies for human capital than quantitative measures, the literature on the relationship between climate shocks and human capital has focused on the latter. By using two unique datasets, one linking test scores with students’ socioeconomic characteristics, and the other containing the climate-related events at the municipal level, this paper contributes to the literature by providing a better estimate of the human capital costs of climate shocks. The findings indicate that the climate shocks of 2010 had a strong negative impact on the test outcomes, especially on those of low-income students; the impact was stronger on male and urban scholars; moreover, having experienced previous shocks seems to have lessened this impact, which points to the importance of adaptation and coping strategies; finally, health deterioration and physical capital destruction could have been two of the channels of transmission, due to the increase in the number of malaria and dengue cases, diseases that are related to weather conditions, and the damaged of school buildings, which might prevent students from attending classes.

Key words: Climate Shocks, Natural Disaster, Human Capital, Cognitive Skills, Colombia.

JEL codes: O12, I20.

Introduction

Using two unique datasets, and applying a difference-in-difference framework with repeated

cross-sections, this paper investigates the impact of the severe weather shocks that affected

Colombia in 2010-2011 on the results in the country’s state standardized test “Pruebas Saber 11” in

the period 2010-2012. Understanding the factors behind the performance of students in national

standardized tests is important since these results operate as a market signaling of the student’s

skills and knowledge; they also allow some students to continue studying at a higher education

level, as some universities not only require the test scores as part of their application process but

also use them to rank students, and so they are important for promoting social mobility.

      

1 Email:  [email protected]. The  author would like to thank  Adriana  Camacho  (thesis 

supervisor) Marcela Eslava, Catherine Rodríguez, Fabio Sánchez, and Alexis Munari for their valuable  comments, and Guberney Muñetón for mapping some of the variables shown in this paper. The author is  solely responsible for any errors or mistakes that may remain.  

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By using a qualitative proxy of human capital, such as cognitive test results, this paper will

contribute to the literature on the relationship between human capital and natural shocks. This

literature has focused primarily on quantitative proxies of human capital, such as years of schooling,

school enrollment ratios, students’ attendance or adult literacy rates. However, recent research on

human capital and educational systems is focusing more and more on qualitative measures of

educational attainment, such as cognitive skills (test score results), at the individual level, or a

country’s quality of education, at the aggregate level, rather than on quantitative measures. This is

because qualitative measures seem to be better predictors of economic growth and income

distribution, but also of individual’s future career success and productivity (Wößmann, 2003;

Orazem, 2007; Baird, 2012). Moreover, time spent in school does not necessarily translate into

more knowledge or better skills, since this variable is not a schooling outcome, but a component of

the educational production process (Orazem, 2007). In fact, differences in adult earnings are better

explained by cognitive achievements than by years of schooling (Glewwe, 2002, cited by Orazem

2007), as suggested by evidence for the United States and the United Kingdom (de Coulon et al.,

2011). Plus, cognitive tests results account for differences in the quality of education, one of the

cornerstones in the theory of human capital (Wößmann, 2003).

As argued by Orazem (2007), the use of measures of learning attainment in economics is still

a nascent field, subject to the availability of periodic academic datasets linking student’s scores with

student and family characteristics. So, previous studies on the relationship between climate shocks

and human capital have analyzed the impact of natural disasters only on quantitative indicators of

human capital; but so far there have been no studies to account for the effects of these disasters on

quality indicators of education. There is also a lack of studies on this relationship for Colombia,

although this country has suffered from several natural disasters in its past. In this sense, the use of

two unique datasets for Colombia, ICFES dataset and SNPAD dataset, allows this paper to measure

the impact of natural shocks on a qualitative proxy of human capital, such as learning attainment

(cognitive skills). ICFES dataset comprises “Saber 11” test scores (a national standardized test,

similar to SAT) plus the personal characteristics and family background of each individual

test-taker; and SNPAD dataset provides information on the natural disasters that have affected

Colombia’s municipalities since 1998.

The theory of human capital, proposed in the 1950s and 1960s by Schultz, Mincer, and

Becker, brought to the spotlight of development economics the importance of education and

accumulation of knowledge. From this theoretical point of view, education can be considered as an

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education (micro level), but also to nations as a whole (macro level). In fact, the theory states that a

great part of the differences in wages are due to differences in the productivity of individuals, but

productivity is itself determined by previous investments made by these individuals in education

and training (Cahu and Zylberberg, 2004). Human capital is then a key element in the development

of nations; it enhances the welfare and the choices available to people (Nahapiet, 2011), but at the

same time it fosters economic growth (Barro, 2001). As Becker states:

The 21st century is clearly placing much greater emphasis than ever before on the importance of knowledge and information to the development of both countries and individuals (…) This means that it is more important than ever for both individuals and for nations to acquire knowledge, skills, and the experience to know how to acquire additional information (Becker, 2011, p. xv).

However, the stock and the accumulation of human capital can be threatened by the

uncertainty of climate shocks. These shocks, similar to economic downturns, will have an influence

not only on the returns of education for the people affected by the shock, but also on their attitudes

towards acquiring human capital (Broomhall and Johnson, 1994). The issue of natural disasters is

even more relevant to human capital if we consider the state of education in developing countries.

In these countries, the limited capacity in human and financial resources is one of the main reasons

why the quality of education is so low, with students learning much less than they should, according

to their curriculums, and also learning less compared to students in developed countries (Glewwe

and Kremer, 2006). In this scenario, climate shocks will make the convergence of these countries to

the quality standards in education reached by the developed world even more difficult.

Over the last hundred years the world has experienced a serious threat to its existing forms of

living: a significant warming, as a result of the increase in the emission of greenhouse gases. This

phenomenon has had regional and global consequences, such as: reduced soil moisture,

precipitation, droughts, sea level rise, high-temperature events, and floods, among others. Models

projections conclude that the average annual global temperature for the period between 2007-2027

will rise about 0.2°C per decade, the average sea level will increase by 0.1 to 0.2 meters by

2090-2099 (relative to 1980-1999), and the frequency of climate shocks, such as heavy precipitations, hot

extremes, and heat events, are very likely to increase in the next 100 years (IPCC, 2007). Moreover,

the wide range of those projections generates uncertainty in terms of the regional and local

socio-economic impacts of climate change (Yohe and Schlesinger, 2002).

Even though climate shocks are part of the history of mankind, the increasing rate of

occurrence of such events and its devastating effects on the lives of millions of people around the

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percentage of the world population still depends on agriculture as its primary source of income, and

many of the people living in the surroundings of the urban areas (slum dwellers) live in deplorable

conditions. For these people, even small changes in climate can have an enormous impact, due to

the nonlinearity response of economic and social systems (Sachs, 2006). Climate shocks might

destroy crops and negatively affect not only people’s assets and savings, but also their health,

nutrition, and education. This implies uncertainty, vulnerability, and fewer opportunities to

overcome their current living conditions, creating cumulative vicious cycles of disadvantages that

are transmitted from generation to generation (UNDP, 2007).

What is more, those risks and vulnerabilities related to climate change are increasingly faced

by poor people (UNDP, 2007; The World Bank, 2010). Indeed, during the period 2000-2004, 1 in

19 of the people affected by a climate shock was living in a developing country, compared with

only 1 in 1,500 for OECD countries (UNDP, 2007, p.76). Additionally, the progressively frequency

and intensity of such events might even compromise the historical resilience of some regions

(Lacambra et al., 2008). In this context, understanding the links between natural shocks and human

development —human capital, in particular, becomes important, especially when designing policies

aimed at reducing vulnerability and enhancing the inherent resilience of regions and communities.

To sum up, climate change will increase the risk of exposure to climate shocks, mainly for the

people living in poor countries, and therefore, will become an obstacle to the development goals of

developing countries.

Colombia is a natural disaster hotspot. According to de la Fuente (2012), Colombia ranks at

number 11 in the global ranking of population in areas of risk; 21.2% of its territory is at risk from

two or more natural hazards; 84.7% of the population living in these areas could be potentially

affected; plus 86.6% of the GDP of risk-prone areas is at stake. According to the National System

for the Prevention and Attention of Disasters (SNPAD, 2013), since 1998, there has been an

increasing rate of occurrence of climate shocks events in the country, as well as a raise in the

number of people affected. From 1998 to 2011, the average annual increase in the number of

climate-related events was 23%. Floods and landslides accounted for 50.6% and 20.5% of all

events, respectively. While in 1998 258,341 people were victims of climate-related disasters, in

2010 this figure was 3,319,686.

What is more, the severe weather shocks of 2010 were the worst experienced by Colombia in

its recent history. To mention just a few statistics, with respect to the previous year (2009), the

number of people affected in 2010 increased in 661% (3,319,686), the number of families affected

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damaged in 519% (376,349), the number of roads destroyed in 358% (1,104), and the number of

schools affected in 351% (501). The shock was not only intense, but was also felt in almost the

whole territory. In 2009, 513 municipalities were affected by climate events; in 2010 this figure

rose to 1,020 (more than 90% of all Colombian municipalities). Moreover, the shocks persisted in

2011, although to a lesser intensity. The Graph 1 shows the number of people (per 100,000

inhabitants) and the number of municipalities that were affected by climate-related events during

the period 1998-2012. The year 2010 stands alone as the most intense year in terms of the severity

of climate shocks. Therefore, this particularity provides a unique opportunity to conduct a natural

experiment and apply an impact evaluation methodology, such as difference-in-difference, to assess

the impact of this severe change in the intensity of climate events on the schooling achievement of

high school students, as measured by the results in Saber 11 test.

Graph 1. Intensity of Climate Shocks in Colombia, 1998-2012 (number of municipalities

affected times number of people affected by climate-related disasters)

Source: SNPAD, author calculations.

This paper is structured as follows. Section I presents a literature review on the relationship

between climate shocks and human development, it also includes some illustrative empirical studies

relating climate events and human capital, and the importance of perceived future risk in the human

capital investment decisions of households; Section II identifies the main determinants of schooling

outcomes, especially those related to student characteristics, parents’ and peers’ characteristics, and

school and teacher characteristics; Section III introduces the datasets used in this paper and some

summary statistics; Section IV explains the empirical strategy of difference-in-difference estimation

with repeated cross sections; Section V presents the main results; Section VI introduces two

0 200 400 600 800 1000 1200

0 500000 1000000 1500000 2000000 2500000 3000000 3500000

1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

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possible channels of transmission: health deterioration and schools buildings destruction, and

discusses the possible implications of credit constraints; finally, the last section concludes.

I. Literature Review

A. Climate Shocks and Human Development: Theory

The effects of natural disasters on economic growth (one of the components of human

development) are not clear-cut, since both positive and negative effects are found in the literature,

without providing definite conclusions (Chhibberet al., 2008; Baez et al., 2009; Ferreira and

Schady, 2009; McDermott, 2012). In general, natural disasters reduce the stock of capital in the

economy causing an immediate decrease in the GDP. But, what is the long-term impact of such

disasters on the economic performance of the affected region? On the one hand, authors such as

Cavallo et al. (2010) argue that natural disasters, either large or small, do not seem to have an

apparent impact on the short/long-term economic growth. On the other hand, authors such as

Chhibberet al. (2008), consider the possibility of such impact, by theoretically analyzing four

different yet-to-test scenarios. In the first two scenarios, the long-term growth rate is not affected,

meaning that after the natural shock, the economy will eventually return to its long-term growth

path, either with (scenario 1) or without (scenario 2) a short-term expansion of its production levels.

In the next two scenarios, the long-term growth rate is affected, either negatively (scenario 3),

because of the permanent reduction in the stock of capital, or positively (scenario 4), due to the

technological change introduced by the restitution of capital.

Therefore, the reduction in the stock of capital that results from a natural disaster is likely to

produce a temporary decline in the income and production levels of the affected economy. Now,

what are the possible effects of this chain of events on human capital, especially on schooling

outcomes?

The answer to this question, according to Ferreira and Schady (2009), will depend on the

magnitude of two opposite forces: the income and substitution effects. The income effect, by

reducing households’ available resources, has a negative impact on schooling; while the substitution

effect, by affecting the opportunity cost of studying versus working (with more children studying

after a shock, due to a reduction in child wage), has a positive impact on schooling. As a result, the

total impact of a natural shock on schooling is not clear cut, especially if households are

credit-constrained; however, in the case of poorer countries, the authors claim, the income effect is

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(contrary to the case of richer countries). For middle-income countries, like those of Latin America,

empirical evidence suggests that education outcomes are counter-cyclical to economic downturns,

meaning that more children are enrolled in school during economic crisis. Nevertheless, the authors

state that the effects are heterogeneous within and across countries. In this sense, natural shocks

have differential effects depending on gender (women usually suffer the most, Goh, 2012), race,

socioeconomic status, occupation, and location, but the poor are always the most negative affected

(Ferreira and Schady, 2009; Baez et al., 2009).

In fact, climate-related events increase the odds that a household remains or becomes poor

(Glave et al. 2008, for the case of Peru); in fact, these events increase the chances of poverty

persistence (poverty lock-in) and downward mobility (downward consumption trajectories),

hindering the capacity of households for rising to a higher socioeconomic position (Premand and

Vakis, 2010). To this effect, natural disasters (especially floods and droughts) have negative

impacts on both human development (deterioration in the human development index) and poverty

(food poverty, capacities poverty, and asset poverty) (Rodríguez-Oreggia et al., 2010). Moreover,

the long-term effects of these events on human development are felt stronger on poorer regions,

because, even though these regions are more prone to natural catastrophes, they are also less likely

to mobilize reconstruction funds, by, for example, implementing counter-cyclical fiscal policies

(Cavallo and Noy, 2010); plus, these regions usually have lower levels of infrastructural

development, awareness, and coping capacities (Goteng et al., 2012). Accordingly, it is stated that

economic and human development can counteract the negative effects of climate shocks on a

certain region; that is, it increases its resilience (Toya and Skidmore, 2007).

The literature has also acknowledged the existence of direct and indirect effects on human

capital derived from climate-related events. Direct effects include the destruction and depletion of

physical and human capital. One of the immediate consequences of climate shocks is the

destruction of physical capital, such as schools, health centers, households’ assets, and public and

private infrastructure; as well as of human capital, in terms of the casualties, disabilities, illness, and

injuries of students, teachers, and health professionals (Fuentes and Seck, 2007; Baez et al., 2009;

Crespo-Cuaresma, 2010; McDermott, 2011). Wounds and illness keep children from attending

school; death translates into a loss in previous investments in human capital; and disease or

epidemics eruption, which results from contamination or scarcity of water and food supplies,

combined with the favorable conditions for microorganisms to emerge and spread, could

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Together, the destruction of physical and human capital increases the marginal cost of

acquiring human capital (Baez et al., 2009), which will negatively affect its future accumulation

and, therefore, the human development possibilities of the affected region.

The negative impacts of the direct effects are certain, but the indirect effects can either

counteract or reinforce these impacts. Contrary to the direct effects, the indirect effects will be

affected by the decisions taken by households after the natural disaster (McDermott, 2012). The loss

of households’ assets, the illness or death of households’ members, which could potentially cut their

available time to generate income, together with the migration and evacuation decisions, will most

probably reduce the family income (Baez et al., 2009; Crespo-Cuaresma, 2010; McDermott, 2011).

Plus, the destruction of infrastructure will require investment decisions by the affected households;

but, poorer families will find it difficult to invest, because of credit restrictions or unavailability of

credit to them. In such situation, credit-constrained households will be forced to disinvest, by

selling-off productive assets, in order to cope with shock. Therefore, this situation will trigger a

vicious circle, since the reduction of productive assets will diminish their ability to generate income

in the future, and this will translate into more vulnerability to future climate shocks (McDermott,

2011). In consequence, when households are credit-constrained, this shock on income will lead

family units to reduce their investment on human and physical capital accumulation. In particular,

the consumption of food, health and educational services will decline. Plus, parents might resort to

children’s time as a buffer mechanism to soften the shock. In this scenario, adding the possible

health impacts derived from the disaster and the possibility that income losses might increase the

opportunity cost of studying, children will be permanent or temporary withdrawn from school (Baez

et al., 2009; McDermott, 2011).

Prices and wages, the amount of parental time, and the discontinuation of schooling are other

indirect channels through which natural disasters affect human capital. The impact of a natural

disaster on prices and wages is unclear, because it will depend on the direction and size of the

income and substitution effects (Baez et al., 2009; Ferreira and Schady, 2009). Additionally, there is

uncertainty about the amount of parental time with children available after a shock, as well as of its

effects on the production of human capital (possibly increasing its marginal cost, Baez et al., 2009).

Finally, because of the discontinuation of schooling, children might not be able to keep up at a later

time or will drop out of the educational system for good, creating a path-dependent effect (Baez et

al., 2009). So, the short-term trade-offs faced by households in order to smooth consumption can

have long-lasting negative effects on the accumulation of human capital, even more when human

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(Fuentes and Seck, 2007). In this sense, the evidence supports the fact that the net effect of the

direct and indirect effects is strongly negative and long-lasting (Baez et al., 2009).

B. Climate Shocks and Human Capital: Empirical Evidence

As was stated in the previous section, the occurrence of natural disasters not only increases

mortality risk, affecting the stock of human capital (because of the casualties of educated persons),

but also affects the decisions of families regarding the use of child labor, in order to compensate for

the income losses from the disaster. These hypotheses have been confirmed by different empirical

studies. For example, using Bayesian Model Averaging methods, Crespo-Cuaresma (2010) finds a

strong negative long-run effect of natural disasters on the rate of secondary school enrollment, a

proxy for human capital accumulation. His results are consistent across countries and robust to

different model specifications. The use of child labor to compensate for income losses is evidenced

by Duryea et al. (2007) for the case of Brazil; in this study, the authors analyze the impact of

household economic shocks on the reallocation of children’s time from school to work; their results

indicate that transitory unexpected economic shocks force families to increase children’s labor in

detriment of children’s schooling.

Early life natural disasters have also been documented to have a negative effect on children’s

future human capital. Studying the case of rural Vietnam, Thai and Falaris (2011) find that negative

climate shocks during gestation and early life affect households’ income, by destroying crop

production, and thus, have an indirect effect on children’s nutrition, measured as height-for-age, and

on schooling, measured as delayed entry to school and slower progress once enrolled. The effects

vary by region, which shows dependence on specific region’s constraints, with the regions where

households face greater difficulties to smooth consumption being the most affected by the shock. In

the case of Mozambique, a similar result in terms of children’s nutrition was found by Prado

(2009): Natural disasters negatively affect children’s height-for-age for children between one and

three years old. In the case of Mali, according to De Vreyer et al. (2011),early life shocks, like the

one experienced by Malians in their early childhood back in the period 1987-1989, when a locust

plague hit the country, have a long-lasting effect on nutrition and, thus, on educational enrollment

and completion. The study shows a differential effect on girls and boys, confirming the

gender-discrimination situation of the country, and a lack of insurance mechanisms that could have helped

smoothing consumption.

Another case study, this time for Colombia, reaffirms the negative effects of climate shocks

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coffee-growing region of Colombia had a negative short-term impact on schooling and nutrition (the

impact persisted in the medium-term, although with a lesser intensity), with parents reducing their

investments in the human capital of their children. Their findings support the hypothesis that one of

the households’ mechanisms to cope with natural disasters is reducing their investment in their

children’s human capital, by withdrawing them from school or impoverishing their nutrition. Plus,

even when remedial actions are taken right after the shock, a natural disaster might have persistent

effects on the accumulation of human capital, with negative long-term welfare effects.

So far, most of the studies have focused on the negative effects of climate shocks on human

capital. Still, climate shocks can also have positive consequences through a sudden increase in

income. For example, for the case of Indonesian adults, Maccini and Yang (2009) studied the

impact of early-life shocks (higher rainfall) on economic development variables, including health,

education, and household’s assets. Their results point out that higher early-life rainfall has a positive

effect on women’s variables (resulting in higher socioeconomic status), but not on men’s, stressing

the gender discrimination issues of the Indonesian society. The channel through which higher

rainfall influence the future socioeconomic status of women is through its impact on agricultural

production, which, in turn, will increase household’s income, improving, later in life, their health

status and schooling attainment.

C. Perceived Future Climate Risk and Human Capital

Human capital is not only affected by actual climate shocks; the perceived future risk,

whether it materializes or not, can also have a profound impact on this variable. For instance,

evidence from rural Indonesia suggests that parents’ schooling decisions are affected by

environmental risks; more precisely, under riskier environments parents tend to postpone their

children’s entry into school (Korkeala, 2012). Moreover, the effect of a perceived future risky

environment, decomposed into household and village effects, on the stock of human capital of

Indonesian rural children, indicate that village-level risk (the aggregate component), such as past

fluctuations in rainfall, has a negative effect on children’s educational attainment, while

household-level risk (the idiosyncratic component), such as risk in parental income, has not significant effect

(Fitzsimons, 2007). These findings point out the difficulty of households to insure against

village-level risks, and therefore, their need to resort to child labor, in order to buffer against the shock;

these results suggest also that the market for this insurance type might be incomplete (Fitzsimons,

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So, focusing only on current shocks and the ex-post responses of households to them might

not provide a full picture of the total costs derived from income risk, as a result of a climate shock,

especially if education exhibits non-linear returns (Kazianga, 2012) or if the effect of future disaster

risk on asset holding is not linear (Yamauchi et al., 2009). On the one hand, the results of Kazianga

(2012) from rural Burkina Faso, although suffering from external validity, indicate that income

uncertainty (income standard deviation) has a negative effect on household schooling decisions.

This is because, in such uncertain environments, parents might decide not to enroll some of their

children in school and put them to work, in order to minimize the impact of future shocks, even if

these shocks do not materialize. On the other hand, if disaster probability is higher than a certain

threshold, then asset holding will be positive; however, future risk has two opposite effects: it

incentives investments, so as to lessen the impacts of future disasters; but it also disincentives

investments, due to the uncertainty of the returns of these investments in front of a future risk

(Yamauchi et al., 2009). In this line of reasoning, the study of Yamauchi et al. (2009), for

Bangladesh, Ethiopia and Malawi, finds that the former effect is greater than the latter in disaster

prone regions. In a similar study, these authors conclude that human capital investments and asset

holding prior to a natural disaster shock help both increasing resilience and upholding investments

in human capital in the aftermath of a shock (Yamauchi et al., 2009b).

II. Determinants of Schooling Achievement

According to the literature, schooling achievement is the result of student characteristics,

parents’ and peers’ characteristics, and school characteristics.

A. Student Characteristics

This section describes the main factors associated to the student personal characteristics that

have been found to be important in determining schooling outcomes, such as test scores. These

characteristics include students’ personality traits, health, time allocation, labor decisions, and

gender.

Students’ personality traits, although not easily measurable, have an important role in

explaining schooling outcomes. For example, Baird (2012) argue that, while for some countries

school characteristics (measured as school resources) still account for a great part of the

performance gap between low and high socioeconomic status students, factors such as students’

effort, interest, and motivation (usually, unmeasured characteristics) are generally more relevant to

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self-esteem tend to create virtuous circles of achievement, because, by trusting in their own abilities,

these students put more effort when performing a task, and, therefore, tend to accomplish more,

reinforcing the circle (Darolia and Wydick, 2011). A prior positive academic self-concept (students

who think of themselves as being more able, effective, or confident) have also an important positive

impact on different schooling outcomes, such as interest in the subjects, grades, and scores in

standardized tests (Marsh et al., 2005).

Children’s health has also strong and significant positive causal impact on their academic

outcomes (Wolfe, 1985; Behrman, 1996; Glewwe and Miguel, 2008). One example is provided by

Sabia (2007), who, after controlling for unobservable heterogeneity, finds that obesity, measured

with a body mass index, has a negative impact on schooling outcomes (GPA) of white girls between

14 and 17 years old (the results are less significant for boys and nonwhite girls). Another case is

given by Belot and James (2011), who exploit a shifting towards healthier meal options in

Greenwich’s schools in the UK; their results suggest that a better nutrition, which translates into

better health, improves student’s schooling outcomes and decreases absenteeism.

Similarly, Time allocation and labor decisions have an important effect on schooling

achievement. Focusing on the effects of time allocation of undergraduate students on their academic

results, although the results suffer from endogeneity, Grave (2011) finds that work group and

attending tutorials has a negative impact on grades for below-average students, as well as for

Engineering and Science students; attending courses has a positive effect only for certain groups of

students (high-ability students and females) or certain programs (Engineering and Social Sciences);

while, the time allocated to self-study or working as a tutor or academic assistant is positively

related to higher grades for all students. Now, concerning labor decisions, Montmarquette et al.

(2007) find that working less than 15 hours a week has not necessarily a negative impact on

schooling outcomes; however, students who actually have an intensive work and non-worker

students who show a preference for intensive work, which indicates a predisposition to a paid-job

over studying, are related to low academic achievement (Staff et al., 2010). The preferences of

studying over working have been found to be related to being female, having educated parents, and

attending a private school (Montmarquette et al., 2007).

Finally, gender seems to have an important effect on academic results, which might stem

from inherently gendered behaviors. Niederle and Vesterlund (2010), for example, argue that

differences in the way men and women respond to competitive test-taking settings are responsible

for the observed gender-related gap in mathematics achievement. These difference responses to

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women, which should actually be regarded, in the author’s words, as “math skills under competitive

pressure”. In consequence, single-sex education can have a positive impact on females’ math

scores, by influencing their math studying decisions and improving their self-confidence in the

subject (Fryer and Levitt, 2009, cited by Niederle and Vesterlund, 2010).

B. Parents’ and Peers’ Characteristics

People whom students interact with in their daily lives, basically parents and friends, play

also a major role in school achievement.

In the case of rural students, Broomhall and Johnson (1994) analyze the value that people

from rural areas place on education. Their results suggest that the value parents put on schooling

together with the availability of local economic opportunities (or the willingness to find better

opportunities somewhere else) exert an influence on the importance rural students place on

education, which in turn translates into a better student’s performance at school. Therefore, parents’

perception of the benefits their children can reap from education combined with the socioeconomic

conditions of the environment will have a say, in terms of incentives, in the student’s and parent’s

decisions on how much to invest in education, and therefore, on the accumulation of human capital

of individuals.

Apart from family income, which affects student’s academic outcomes, mostly through the

impacts of school choice proxies (Hoxby, 2001, cited by Krieg and Storer, 2008), the literature has

found other parents-related variables that explain to a certain extent schooling performance.

Parent’s cognitive skills, for instance, are highly correlated with their children’s academic

achievement at school; plus, children of parents with higher cognitive skills are likely to perform

better in tests and to have less behavioral and emotional complications (de Coulon et al., 2011).

Literature for college performance indicates that parents’ reward schemes will exert an influence on

their children’s academic effort and on their post-school achievement (Darolia and Wydick, 2011).

Allowances seem to have a negative to neutral effect on these variables, except if the allowance was

given upon the completion of a certain task (conditional allowances), in which case the effect was

positive; purchasing a car in high school relates to a lower academic effort; but, children of parents

who usually recognize their achievements, by influencing their self-esteem, will tend to exert

greater effort in their undergraduate studies (Darolia and Wydick, 2011).

Research on parental closure found mixed effects of this variable on student’s high school

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and Todd, 2009). Paternal job loss has a negative impact on children’s schooling outcomes,

although not maternal job loss, which has a non-significant positive effect on the student’s GPA, at

least for the Norwegian case; this difference is explained by the claim that men experience more

mental distress from a job loss experience than women (Rege et al., 2011). Birth order has no

significant effect on test performance, but the number of siblings does negatively impact verbal IQ

results (Steelman and Doby, 1983); the reasons provided by the authors are related to the

importance for language development of parents’ interaction with their children, in terms of

stimulation and attention, which could be considerably affected by the number of siblings that

would have to compete for their parent’s time and dedication.

This latter result was also confirmed by Zimmerman (2003), when analyzing the effects of

peer roommates on test scores. The author’s results suggest that peer roommates have a more

positive and significant effect on verbal tests scores than on math tests scores. Other studies have

also remarked the importance of peers in schooling performance. Focusing on 11 years old British

children, Robertson and Symons (2003) found a strong effect of peer groups, parents’ education,

and social class on children’s academic achievement. Peer effects explain also, to a great extent, the

reasons behind the performance gap between primary school students from Mexico and Cuba (with

Cubans outperforming Mexicans) (McEwan and Marshall, 2004); in this study the socioeconomic

variables of the student’s family appear to be also important, although to a lesser degree; while

school and teacher characteristics have no explanatory power when explaining differences in

academic achievement across nations. Analyzing the United States case, Lee (2007) finds that both

peer racial composition and school have significant effects on the student’s academic outcomes.

C. School Characteristics

Most of the interaction between students and their peers and teachers occur in school

environments, hence the importance of this variable in schooling performance. As in the case of the

number of siblings, the number of students in a class might limit the time a teacher could spend

with each of her pupils. In this respect, some research has found that class size reductions and

teacher density (number of teachers per student) might exert a positive influence on cognitive skills

and academic achievement (Fredriksson and Öckert, 2008; Ding and Lehrer, 2011), but the

evidence is not clear-cut in the case of non-cognitive skills, such as motivation, listening, and

self-concept, in which case family background seems to be more important (Ding and Lehrer, 2011).

Results from a natural experiment and a field experiment suggest that attending a high-scoring

school has a positive impact on the student’s own academic achievement (Hastings and Weinstein,

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great part from the socioeconomic characteristics of their students rather than from the school

quality (Krieg and Storer, 2008). The literature points also to the importance of remedial summer

schools and retention programs on academic achievement, especially for young disadvantaged

students (Jacob and Lefgren, 2004).

Teacher quality has been considered an important factor affecting students’ cognitive skills.

In this respect, focusing on public elementary education, Rivkin et al. (2005) argue that teachers’

quality have an important effect on student’s mathematics and reading performance (and therefore

on the school quality), and that being exposed to a higher quality teaching environment can

counterbalance the negative effects of having a low socioeconomic status. However, the authors

found that teacher quality is mostly explained by the unobservable characteristics of the teacher,

since years of experience or having a master degree does not seem to have any significant impact.

At the international level, Glewwe and Kremer (2006) highlight the importance of teacher’s quality

as the most important factor affecting school quality and its cross-country differences. Their claim

is supported by random experiments conducted in different developing countries, where the

substitution of technologies, such as radio education in Nicaragua or computer-assisted learning

programs in India, for weak teachers have had a positive effect on the student’s academic outcomes;

this assertion is also supported by the results found after the implementation of teacher incentives in

countries such as Israel and Kenya, where student’s performance and test scores were significantly

improved (although only on short-run outcomes, in the case of Kenya, and mainly for weaker

students, in the case of Israel).

Lastly, central exit examinations have a positive impact on student’s academic achievement,

(Jürges et al., 2005), but this impact seems to have differential effects, depending on the ability of

students; that is, central exit examinations have a lesser impact on low-ability students, compared to

high-ability students, due to the characteristics of the labor market for less skilled workers (lower

job mobility and limited grades-reading capacity of local employers) (Wößmann, 2005).

III. Data

This paper uses two different unique databases: ICFES database for Saber 11 test and

SNPAD database for natural disasters. The ICFES database contains the test results from the

examination Saber 11, a standardized national test applied to high school Colombian students prior

to graduation. The test is developed by the Instituto Colombiano para el Fomento de la Educación

Superior —ICFES (Colombian Institute for the Promotion of Higher Education). The purpose of the

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a year, according to the academic year of the school; however, for most of the institutions the

academic year starts in late January or early February and ends in mid or late November; this

calendar is known as “calendar A”. The test results are required by some universities as part of their

application process; they also serve as a quality indicator that allows comparing the country’s high

schools performance. Now, regarding the contents of the Saber 11 test, the test has two components:

a common core, which evaluates the students’ knowledge in eight (8) different subjects: language

(Spanish), mathematics, biology, chemistry, physics, philosophy, social science, and foreign

language (English); and a flexible core, which allows students to choose one subject out of the six

available options, divided in four in-depth subjects: language, mathematics, biology, or social

science, and two interdisciplinary subjects: environment or violence and society.

This paper uses the Saber 11 (calendar A) database for the period 2008-2012. Specifically, it

uses the following information from the database: test results, student characteristics, and household

characteristics. Test results include the test scores for each of the subjects of the common core

(language, mathematics, biology, chemistry, physics, philosophy, social science, and English) —the

total score was calculated as the arithmetic mean of the common core components. Student

characteristics include: date of birth (three age variables were constructed from this information:

age —the student age when the test was taken, age 15-16 —a dummy variable if the student was 15

or 16 years old, and age-squared); mother education and father education, which ranks the student

parents’ level of education on an ascending scale from 0 to 10 (where 0 means “none education”

and 10 “graduate studies”); sex (male or female), from which the dummy variable male was

created; and work, a dummy variable if the student had a job (paid or not) (the original database had

different job classifications, which were recoded into just one category).

Household characteristics include: social stratum (the social stratification by law, ranging

from 1 to 6 —1 indicating the lowest and 6 the highest, with each strata sharing similar

socioeconomic characteristics; a few students classified as a strata 8 —not stratified, were omitted

from the database); Sisben —El Sistema de Identificación de Potenciales Beneficiarios de

Programas Sociales (The System for the Selection of Beneficiaries of Social Programs), ranging

from level 1 to 4 (level 1, 2, and 3 means that the household is classified in any of these levels,

whereas level 4 includes households that are classified at a different level and those that are not

classified at all), monthly household income (income), ranging from 1 to 7, according to the number

of minimum wages earned by the household unit on a monthly basis (1: less than 1 minimum wage;

2: between 1 and 2; 3: between 2 and 3; 4: between 3 and 5; 5: between 5 and 7; 6: between 7 and

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the variable No. of people per dormitory and overcrowding (d) (dummy if the variable No. of people

per dormitory was equal or greater than 2.5) were created; living zone (urban or rural), from which

the dummy variable urban was constructed; and, finally, the dummy variables: car, computer, and

DVD player, each indicating whether or not the household had at least one of these objects, and

Internetconnection and cableTV, each indicating if the household had the service installed (some

variables in the original database specified the number of objects the household had, these were

recoded to “having at least one”).

From the ICFES database, the variable total score is used as dependent variable, whereas the

student and household characteristics are used as controls. The total number of students in the

database for the period 2008-2012 is 2,669,540. Some summary statistics for some of the main

variables as well as the total number of students per year are presented in Table 1.

Table 1. Summary Statistics for ICFES Database Variables, 2008-2012

Category  Variable  Obs.  Mean  Std. Dev.  Min.  Max. 

Saber 11  Scores 

Total score  2,652,365  44.137  6.447  0.000  87.125 

Biology  2,653,386  45.292  8.172  0.000  100.000 

Social Science  2,653,386  44.759  9.237  0.000  112.930 

Philosophy  2,653,386  40.552  9.265  0.000  84.000 

Physics  2,653,386  43.875  8.407  0.000  112.000 

English  2,652,365  42.947  10.084  0.000  111.940 

Language  2,653,386  45.798  8.320  0.000  93.000 

Mathematics  2,653,386  44.763  10.644  0.000  126.000 

Chemistry  2,653,386  45.090  7.419  0.000  94.640 

Year 

2008  508,253  ‐  ‐  ‐  ‐ 

2009  521,738  ‐  ‐  ‐  ‐ 

2010  540,452  ‐  ‐  ‐  ‐ 

2011  540,441  ‐  ‐  ‐  ‐ 

2012  549,832  ‐  ‐  ‐  ‐ 

Source: ICFES, Saber 11 database, author calculations.

The ICFES database variables were merged with some variables from the SNPAD national

disasters database. This database was developed by the governmental institution “Sistema Nacional

para la Prevención y Atención de Desastres” (National System for the Prevention and Attention of

Disasters). The database contains the records of the different natural events that have affected

Colombia since 1998 at a municipality level. Some of the variables included in the database are:

date of the event; municipality code; type of event; number of casualties; number of people

affected, wounded, or missing; number of houses destroyed or damaged; and number of different

public infrastructure affected.

In order to create a shock variable (shock), the following variables were used from the

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construction of the variable shock is detailed as follows. For each year and for each Colombian

municipality, the number of people affected by natural disasters per 100,000 inhabitants was created

(see Map 1 for the year 2010). This variable was used afterwards to calculate the average of the

annual gross changes between 2004 and 2009, as well as the gross change between 2009 and 2010.

The 2004-2009 average was then compared with the 2009-2010 gross change using the percentiles

50 and 99. This information was used to select the treatment and control groups. A municipality

was considered treated with intensity 1 if the 2009-2010 gross change was greater than the

percentile 50 but less than the percentile 99 of the 2004-2009 average (shock=1), and it was

considered treated with intensity 2 if the 2009-2010 gross change was greater than the percentile 99

(shock=2) of the 2004-2009 average. If the 2009-2010 gross change was less than or equal to the

percentile 50 of the 2004-2009 average, the municipality was included in the control group.

The reason why the shock variables were used as indicators of treatment is because the

impact of the natural disasters on the test scores does not seem to follow a linear pattern (as

suggested by Sachs (2006) in terms of the non-linear effects of climate change). In fact, the impact

of the variable “number of people affected by 100,000 inhabitants”, when included as a explanatory

variable of the Saber 11 test scores, was close to zero and non significant, indicating that a natural

shock might affect cognitive skills only if it surpasses a certain threshold.

Map 1. People Affected by Climate-Related Events in Colombia, 2010 (Per 100,000

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Source: SNPAD, author calculations.

Table 2 shows some summary statistics for the SNPAD database. In particular, it shows the

number of people affected by climate-related disasters, per 100,000 inhabitants, as well as the total

number of people affected. The source of the municipalities’ populations between 2006 and 2012

was “Departamento Administrativo Nacional de Estadística” DANE (National Administrative

Department of Statistics).

Table 2. Summary Statistics for SNPAD Database Variables, 2006-2012

Variable  Mean  Std. Dev.  Min.  Max. 

No. of  people  affected  Disasters 2006  3,100.3  9,149.0  0  135,656.8  711,447 

Disasters 2007  6,271.9  22,320.0  0  275,423.9  1,559,377 

Disasters 2008  8,932.6  22,490  0  214,432.4  1,877,504 

Disasters 2009  2,274.7  12,593.3  0  345,651.6  435,851 

Disasters 2010  16,614.01  31,605.4  0  577,616.1  3,319,686 

Disasters 2011  11,263.16  26,875.1  0  348,439.5  2,178,557 

Disasters 2012  1,560.78  7,421.7  0  128,402.6  282,333  Source: SNPAD, DANE, author calculations.

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IV. Empirical Strategy: Difference-in-Difference Estimation with Repeated Cross Sections

This paper uses a difference-in-difference estimation with repeated cross sections to measure

the impact of the climate shocks of 2010 and 2011 on the test scores of the Saber 11 test in the

period 2010-2012. The dummy variable shock indicates the treatment status of the individuals, that

is, a student will belong to the treatment group if she lives in a municipality for which the change in

the number of people affected by climate-related disasters (per 100,000 inhabitants) between 2009

and 2010 was either greater than the percentile 50 (shock intensity 1) or greater than the percentile

99 (shock intensity 2) of the average of the annual changes between 2004 and 2009. The student

will belong to the control group if she lives in a municipality where the change in the number of

people affected by climate-related disasters (per 100,000 inhabitants) between 2009 and 2010 was

less than or equal to the median (percentile 50) of the average of the annual changes between 2004

and 2009 (shock=0). Even though shock varies at the municipality level, this paper uses student i as

the unit of observation. The reason for this is the possibility to control for observables available in

the ICFES database, as well as to examine heterogeneous effects. The baseline model is given by

equation (1), whereas the time-heterogeneous effects model is given by equation (2):

2011 ∗ 1

2010 2011 2012 ∗ 2010

∗ 2011 ∗ 2012 2008 2

where the outcome variable represents the test score of student i in time t; is a

dummy variable equal to 1 if the student lives in a municipality j where the shock intensity was 1,

and equal to 2 if the shock intensity was 2 ; post is a dummy variable equal to one in the post-shock

period (2010-2012); y2010, y2011, and y2012 represent dummy variables for the years 2010, 2011,

and 2012; is a vector of student and parents control variables (age, age 15-16 —dummy for ages

15 or 16, age-squared, mother education, father education, male —dummy for student’s sex, and

work —dummy equal to one if the student works), household control variables (social stratum,

sisben, income —monthly household income, No. of people per dormitory, overcrowding (d)

dummy equal to one if No. of people per dormitory is equal or greater than 2.5, urban —dummy

equal to one if the student lives in an urban area, car —dummy equal to one if the household has at

least one car, computer —dummy equal to one if the household has at least one computer, DVD

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dummy equal to one if the household has Internet connection, and cable TV, —dummy equal to one

if the household has cable TV); is a vector of climate shocks variables for the years pre and post

2010 (disasters 2006, disasters 2007, disasters 2008, disasters 2009, disasters 2011, disasters

2012), representing the number of people affected by climate disaster per 100,000 inhabitants;

is a vector of dummy variables to control for 2008, 2010, and 2011 year effects; y2008 is a

dummy variable for the year 2008; represents school fixed effects; and, finally, is an error

term which satisfies | 2010 0.

The difference-in-difference estimator ( ) in equation (1) will be given by ; whereas the

differential effect of years 2010, 2011, and 2012 in equation (2) will be given by ( ),

( ), and ( ). Under the baseline model specification, β1 represents the treatment

group specific effect; β2 is a time trend, which is common to treatment and control groups; and β3 is

the true effect of treatment. In order for the model to be correctly estimated, the following

assumptions are required: (1) the error term must have mean zero, (2) the error term must not be

correlated with any of the variables in the equation, and (3) the parallel-trend assumption, which

guarantees that in the absence of treatment (shock), the average change in the test score for the

treatment group would have been the same as the average change for the control group. Trends in

the average Saber 11 scores for the years before the shock (2008, and 2009) for both treatment and

control groups are presented in Graph 2. Before the shock, the trends in the average scores were

similar for both groups; however, after the shock, the treatment group exhibited a different path.

Graphically, the strongest effects of the 2010-2011 natural events were felt in 2011; but they were

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Graph 2. Parallel-Trend Assumption

Source: ICFES, SNPAD, author calculations.

This paper implements also a triple-difference approach, in order to analyze the

heterogeneous effects, as the literature has pointed out that the impacts of climate shocks on

schooling outcomes vary according to certain characteristics, such as sex or living area, for

example. The triple-difference model specification for the baseline model is given by equation (3),

whereas the triple-difference for the time-heterogeneous effects model is given by equation (4); in

both model specifications, represents a variable for which the expected outcome varies with:

∗ ∗ ∗

∗ ∗ 3

2010 2011 2012 ∗

∗ 2010 ∗ 2011 ∗ 2012 ∗ 2010

∗ 2011 ∗ 2012 ∗ ∗ 2010 ∗

∗ 2011 ∗ ∗ 2012 2008 4

This paper estimates equations (3) and (4) to measure the differential impacts of shocks of

2010-2011 (shock) on the variables male, urban, disasters 2006, disasters 2007, disasters 2008, disasters

2009, social stratum, and income. The triple-differences estimator ( ) in equation (6) is given

by ; measures the impact of the variable shock when Z = 0, and the impact when Z

= 1; and so the estimator identifies the differential impact of the variable shock for Z =

40 41 42 43 44 45 46 47

2008 2009 2010 2011 2012

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1 with respect to Z = 0. In the case of equation (4), the differential impact of shock on the different

values of Z for the years 2010, 2011, and 2012 is given by ( ), ( ), and

( ), respectively.

IV. Results

Graph 3 presents the difference-in-difference estimations of , , and ,

using two different model specifications of equation (2): (1) difference-in-difference without

controls and school fixed effects and (2) difference-in-difference with controls and school fixed

effects. In general, the estimators are quite similar in both cases. However, the negative effect gets a

little bit stronger as controls and fixed effects are added to the simple difference-in-difference

estimation. This fact would imply that the estimation of for the different post-years, without

such controls and fixed effects, might be biased; that is, the control variables and the fixed effects

help explain both the test scores and the fact that the municipality had suffered more from the

2010-2011 climate-related shocks than the national municipality average. However, the estimator would

be biased downwards. For example, studying in a school with poor infrastructure increases the

chances of being affected by a landslide or a flood, augmenting the possibility of being treated, but

it also relates to a lower test score. By the same token, a high household income decreases the

chances of being affected, perhaps by living in a house better equipped to annual floods or by

having access to credit and insurance markets, but it also has a positive effect on the test scores.

Therefore, the effect of the omitted variables on the treatment indicator and on the outcome variable

seems to follow opposite directions, and so not including control variables would underestimate the

impact estimator.

Graph 3. Impact of the Climate Shocks of 2010 on the Saber 11 Test Scores Using (1)

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Source: ICFES, SNPAD, author calculations.

Note: All estimators are statistically significant at 1%. Standard errors were clustered at the school level.

The results shows that the climate shocks of 2010, as measured by the variable shock, had an

important and significant impact on students’ Saber 11 tests scores; the shock was more strongly

felt in 2011, but its intensity had repercussions even in 2012, although to a lesser extent. Despite the

fact that the climate shocks were intense in 2010, these weather-events did not have such great

impact on the 2010 test results, compared to 2011 and 2012; the reason for this is that the 2010

Saber 11 test was taken on September 12th 2010, but (1) most of the natural disasters concentrated

in just two months: August and November, and (2) in terms of the breadth and depth of the

disasters, November stood alone as the time of the year when most municipalities suffered the most

from these events.

Table 3 presents the complete results of the estimation of equations (1) and (2) using pooled

OLS with clustered standard errors at the school level. Students’ and parents’ characteristics, as

expected, have an important impact on the test score, result confirmed by the literature review of

Section II, as well as by the studies on the determinants of academic performance in Colombia

(Chica et al., 2011; Gaviria and Barrientos, 2001). Students’ age is negatively related to test scores,

but having the correct age for grade has positive impact on this outcome; having a job while

studying is related to a lower test performance, and so is being female. All of these variables are

important in the estimation and might help capture some of the students’ unobserved skills and

traits, such as interest or motivation, as well as their possible time allocation. Parents’ level of

education is also important, as it is related to higher levels of income; and by having higher salaries

or belonging to a higher socioeconomic class, parents can have access to higher quality education, ‐0.204***

‐0.708***

‐0.436*** ‐0.26***

‐0.722***

‐0.45***

‐0.8 ‐0.7 ‐0.6 ‐0.5 ‐0.4 ‐0.3 ‐0.2 ‐0.1 0

2010 2011 2012

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to a wider range of school choice (Gaviria and Barrientos, 2001; Krieg and Storer, 2008), and to

school complements, such as personal teachers or assistive technology.

Now, concerning student’s household characteristics, living in an overcrowded house (more

than 2.5 people sharing a bedroom) has a slightly negative effect on test scores, possibly because

the student might have more siblings or relatives living in the same place and so she might not

receive enough parents’ dedication and attention. Living in an urban area is positively correlated

with a better scoring, since urban dwellers might not only enjoy a broader range of academic

services, but put a greater value on education too, because the benefits of investing in education, in

terms of the economic opportunities available after graduation, are broader if the student lives in an

urban area. In this sense, rural students might put a lower value on education, as a result of the

shortage of high quality schools, and the lack of proper incentives to have a good score, as argued

by Broomhall and Johnson (1994). Having at least one computer and Internet connection has a

positive impact on schooling outcomes; these household services can act as a complement of the

education received at school, but also as a substitute for weak teaching (Glewwe and Kremer,

2006). In contrast, having at least one car, one DVD player, or cable TV is related to a negative

score; cable TV and DVD player can take up time that would have otherwise been allocated to

studying, while the negative effect of having at least one car could be related to the parents reward

schemes discussed in Section II (Darolia and Wydick, 2011).

Table 3. Impact of the Climate Shocks of 2010 on the Saber 11 Test Scores, 2010- 2012

Dependent variable: Score Pooled OLS

Baseline Model [eq.

(1)]

Time-Heterogeneous

Effects Model [eq. (2)]

Shock.1 0.095

(0.051)

0.098 (0.051)

Shock.2 0.297**

(0.096)

0.302** (0.096)

Shock.1*Post -0.296***

(0.038)

Shock.2*Post -1.017***

(0.044)

Post 0.925***

(0.032)

Shock.1*y2010 -0.180***

(0.035)

Shock.2*y2010 -0.554***

(0.042)

Shock.1*y2011 -0.408***

(0.05)

Shock.2*y2011 -1.548***

(0.058)

Shock.1*yt2012 -0.306***

(0.044)

Shock.2*y2012 -0.955***

(0.051)

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(0.008) (0.008)

Age 15-16 1.280***

(0.01)

1.280*** (0.01)

Age-squared 0.002***

(0.000)

0.002*** (0.000)

Mother education 0.186***

(0.003)

0.186*** (0.003)

Father education 0.191***

(0.002)

0.191*** (0.002)

Social stratum 0.150***

(0.009)

0.150*** (0.009)

Overcrowding 0.017**

(0.006)

0.017** (0.006)

Overcrowding -0.069***

(0.012)

-0.068*** (0.012)

Income 0.272***

(0.006)

0.271*** (0.006)

Work -0.236***

(0.015)

-0.236*** (0.015)

Male 1.084***

(0.01)

1.084*** (0.01)

Sisben 0.136***

(0.005)

0.136*** (0.005)

Urban 0.490***

(0.016)

0.490*** (0.016)

Car -0.395***

(0.012)

-0.395*** (0.012)

Computer 0.372***

(0.011)

0.373*** (0.011)

DVD player -0.251***

(0.009)

-0.249*** (0.009)

Internet connection 0.114***

(0.012)

0.110*** (0.012)

Cable TV -0.248***

(0.01)

-0.249*** (0.01)

y2008 -0.194***

(0.018)

-0.195*** (0.018)

y2010 -0.116***

(0.015)

0.668*** (0.029)

y2011 -0.403***

(0.016)

0.678*** (0.039)

y2012 0.920***

(0.036)

Disasters 2006 0.000

(0.000)

0.000 (0.000)

Disasters 2007 0.000

(0.000)

0.000 (0.000)

Disasters 2008 -0.000*

(0.000)

-0.000* (0.000)

Disasters 2009 0.000

(0.000)

0.000 (0.000)

Disasters 2010 0.000

(0.000)

0.000 (0.000)

Disasters 2011 0.000

(0.000)

0.000 (0.000)

Disasters 2012 -0.000*

(0.000)

-0.000* (0.000)

Constant 41.551***

(0.118)

41.544*** (0.118)

School Fixed Effects YES YES

R-squared 0.371 0.371

Obs. 2,422,673 2,422,673

Source: ICFES, SNPAD, author calculations.

Notes: (1) *p<0.05, **p<0.01, ***p<0.001, (2) standard errors in parenthesis are clustered at the school level.

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Equations (1) and (2) were also estimated having as dependent variable each of the core

subjects of the test. Table 4 presents the difference-in-difference estimator of the impact of the 2010

climate shocks on each of the core subjects evaluated in the Saber 11 test. In general, the effect of

the shocks was negative and highly significant (except for Chemistry and English). As expected, the

impact was greater in municipalities that experienced a stronger shock (shock=2). The most affected

subjects were Philosophy, Language, Mathematics, and Biology; Language and Philosophy

followed a similar trajectory, which could be an indicator that these subjects require similar skills

and that these skills could have been in turn heavily affected by the climate shocks of 2010.

According to ICFES, Language, Philosophy, and Social Science tests evaluate students’ skills in

interpretation, argumentation, and proposition; the reason why the effect was stronger in the first

two subjects than in Social Science could be related to the fact that Philosophy might be closer to

Language, since it is aimed at improving students’ critical thinking, communication, and reading

abilities. The literature review suggested that the lack of interaction between students’ and their

parents, peers, and teachers have a robust impact on the development of their language skills; then,

one possible explanation for the strong effect of the climate disasters on Language and Philosophy

is that these shocks could have prevented such interactions.

Relatively to other subjects, the effect of the shocks on Mathematics was important (it was

the most affected subject in 2010). The skills evaluated in this subject are: communication,

reasoning, and problem-solving. In the case of Natural Sciences (Biology, Chemistry, and Physics),

which evaluate the identification, enquiring, and explanation skills, the strength of the effects was

different for each subject, being stronger for Biology, and weaker for Chemistry, which was the

second least affected of all common core subjects after English. The shock effect on Social Science,

which assesses the same skills as Language and Philosophy, was comparatively low; while the

impact on English, which evaluates grammar skills, textual skills, and textual coherence, was

generally not significant and had a positive sign in 2011.

As was stated by Niederle and Vesterlund (2010) in Section II, males tend to outperform

females in mathematics. This tendency is also confirmed in this study; in fact, although males

outperform females in all subjects, except Philosophy, Mathematics exhibits the greatest score

differences between males and females, followed by Physics, Social Science, and Biology. Girls

tend to perform better in Philosophy, whereas the advantage of boys over girls in Language is the

lowest among the boys-dominated subjects. This might provide new evidence that performance in

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